Three-dimensional puzzle with seven axes of rotation

ABSTRACT

The present invention discloses a spherical puzzle whose visible segments are delimited by seven planar sections through the center of said sphere and may be permuted by rotations of hemispherical groups of visible segments with respect to any planar section of the puzzle about an axis perpendicular to said section through the center of said sphere. Three planar sections are parallel to the faces of a cube inscribed in said sphere, and the remaining planar sections are perpendicular to the diagonals of said cube. The visible segments comprise eight arcuate equilateral triangles and twenty-four arcuate right triangular triangles. As a novelty, this invention integrates an interlocking mechanism of the arcuate right triangular outer segments to a spherical center support with four axes of rotation, with a slidable spring activated interlocking mechanism of the arcuate equilateral triangular outer segments to their side neighbors.

I hereby claim the benefit of the filing date of a copending Provisional Utility Patent Application, with Application Number 61765053, entitled “Three-dimensional Puzzle with Seven Axes of Rotation”, filed on Feb. 15, 2013.

BACKGROUND OF THE INVENTION

This invention relates to three-dimensional logical puzzles which include a plurality of segments interlocked in a spherical shape, the segments being capable of adopting a plurality of positions relative to one another by a sequence of rotations of hemispherical groups of segments.

DESCRIPTION OF THE RELATED ART

The art of three-dimensional logical puzzles that comprise a plurality of interconnected segments to be unscrambled by rotating some of the segments relative to each other sequentially along planes in space, gained popularity with the advent of Rubik's 3-D twisty puzzles in the early 1980s, including the Cube, Snake, and Pyramid. Since then, several similar puzzles have been invented giving birth to a brand new toy industry and initiating the study of their properties and solving complexity. The rotation of individual pieces or groups of pieces provides a great number of possible combinations of the individual pieces only one or a few of which are solutions. The solutions are pattern or color combinations selected by the creator or manufacturer from all the other possible combinations of the pieces.

Of particular interest are the puzzles comprising segments coupled together to form a spherical shape, and which always involves the relative rotation of two complete half spheres. These inventions are interesting both as standalone embodiments and as parts of more complex mechanisms. The complexity of these puzzles can be appreciated by looking at the number and orientation of their axes of rotation, and at the means to keep the segments interlocked.

One way to interlock the elements comprising the puzzle is by means of a spherical central structure with circular tracks receiving legs and feet of slidable outer segments. The proper alignment of the outer segments with said central part is ensured by fastening one of the outer segments to the central part. Inventions of this kind are disclosed in U.S. Pat. No. 213,030 (T. Isobe) and U.S. Pat. No. 4,478,418 (B. F. Sherman Jr. and S. Francis), which enable the embodiment of a puzzle comprised of eight blocks installed around a central part such that four blocks at a time can be rotated by multiples of 90° about any of three orthogonal axes.

U.S. Pat. No. 4,441,715 (S. C. Titus) discloses another interlocking approach, by means of slidably interlocking connections—arcuate T-shaped slots and complementary arcuate T-shaped studs—between the pieces such that any two interlocked hemispheres can be rotated by 180° relative to each other. The preferred embodiment of this prior invention is a hollow sphere whose outer segments are delimited by planar sections of said sphere having in common a line joining two diametrically opposite poles of the sphere, and can be subjected to rotations by 180° of differing pairs of hemispheres along said planar sections.

U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau) discloses yet another interlocking approach, based on an armed spider whose rotatable tips are the fixed segments of said puzzle. The other segments of the puzzle are coupled with the fixed segments in a spherical shape, and can be permuted by multiple of 120° rotations of hemispherical groups of said segments along planes perpendicular to the four branches of the spider.

U.S. Pat. No. 4,474,377 (J. J. Ashley) discloses a cubical puzzle whose twenty-four exposed pieces may be permuted by rotations of groups of said pieces about any of seven axes passing through the vertices and the centers of the faces of said cube. Unfortunately, this invention is neither intended nor adaptable for puzzles with rotations of hemispherical groups of segments.

What is desired, and not heretofore been developed, is a spherical puzzle with thirty-two exposed segments which may be permuted by rotations of hemispherical groups of said segments about seven axes passing through the center of said sphere. The easiest way to visualize the relative positions of these axes is by drawing a cube whose center coincides with the center of the spherical puzzle: three axes cross the center of the cube and are perpendicular on its faces, whereas the other four axes of rotation are determined by the center and a corner of the cube.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a puzzle in the shape of a sphere with seven axes of rotation and with increased entertainment value. The puzzle has thirty-two visible segments delimited by seven planar sections through the center of said sphere, which may be permuted by rotations along any said planar section. Three sections are parallel to the faces of a cube inscribed in said sphere, therefore the axes of rotation perpendicular to them will be called cubical axes. The remaining four sections are perpendicular to the diagonals of said cube, therefore the axes of rotation perpendicular to them will pass through the vertices of a regular tetrahedron inscribed in said sphere and will be called tetrahedral axes. There are eight visible segments with arcuate equilateral triangular faces and twenty-four visible segments with arcuate right isosceles triangular faces, forming fourteen different hemispherical groups rotatable relative to each other about said axes. The cubical axes are intended for hemispherical rotations of the segments of the puzzle by integer multiples of 90°, and the tetrahedral axes are intended for hemispherical rotations by integer multiples of 120°.

The preferred embodiment of this invention comprises a spherical center support and a plurality of thirty-two outer segments of uniform thickness which enclose completely the spherical center support. The spherical center support is an embodiment of the spherical puzzle disclosed in U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau), modified to include three orthogonal crossing tracks wherein each track forms a complete circle in the support along the diagonals of the arcuate square puzzle segments of said center support, and includes a pair of outer lips extending toward each other to define a narrow outer slot and an inner enlarged sliding path. The said plurality of thirty-two outer segments comprises:

-   -   eight segments of arcuate equilateral triangular shape and         twenty-four segments of arcuate isosceles right triangular         shape, wherein every arcuate segment of equilateral triangular         shape abuts three said segments of arcuate right triangular         shape,     -   legs mounted on said outer segments of arcuate right triangular         shape and extending through the narrow slot of said crossing         tracks of said spherical center support,     -   feet mounted on the inner ends of said legs for sliding in the         inner enlarged paths of said crossing tracks and for being         engaged by inner surfaces of the lips of said crossing tracks to         retain said right triangular outer segments on said spherical         center support,     -   one outer arcuate equilateral segment called anchor, fastened on         top of an arcuate equilateral triangular segment of the         spherical center support,     -   U-shaped slots along all sides of arcuate outer segments         adjacent to the section planes perpendicular to the tetrahedral         axes of the puzzle,     -   spring latching mechanisms mounted on each side of the arcuate         outer segments of equilateral triangular shape, comprising a         tongue which is urged by a spring to protrude from its segment         into the U-shaped slot facing them on the abutting outer         segment.         The spring latching mechanisms keep the outer equilateral         segments in position between the abutting outer segments of the         puzzle, and provides a slidable interlocking connection for         them. The anchor ensures the alignment of the outer segments         with the segments of the center support.

As a logical puzzle, this invention is also provided with some easily recognizable coloring or pattern on the visible faces of the outer segments, such as the assignment of a distinct color to every octant of the sphere comprising one equilateral and three right triangular segments. The puzzle may be scrambled by a series of rotations by integer multiples of 90° about cubical axes and integer multiples of 120° about tetrahedral axes. The object of the puzzle is to return by means of a series of such rotations to the unscrambled coloring or pattern.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of this invention.

FIG. 2 shows two views of this invention subjected to rotations. The left view shows a rotation about a cubical axis, and the right view shows a rotation about a tetrahedral axis.

FIG. 3 is a perspective view of the spherical central support of this invention.

FIG. 4 is perspective view of a typical prior art embodiment disclosed in U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau).

FIG. 5 is an exploded view of the portion of this invention comprising an arcuate square segment of the spherical central support and four right triangular external segments mounted on top of it.

FIG. 6 is a partial section view of this invention with a plane through the center of the puzzle perpendicular to a cubical axis.

FIG. 7 is a is a detailed view of a portion of the spherical central support with legs and feet of arcuate right triangular members of the puzzle shown at a junction of tracks.

FIG. 8 is a perspective view of this invention with the outer equilateral triangular segments of the puzzle exploded outward a common distance from their installed positions.

FIG. 9 is an exploded view of an outer arcuate equilateral segment of this invention.

FIG. 10 is a median cross section view of an outer equilateral triangular segment of this invention.

FIG. 11 is a perspective view of this invention which shows the coupling between its components during a rotation about a cubical axis.

FIG. 12 is a perspective view of this invention which shows the coupling between its components during a rotation about a tetrahedral axis.

DETAILED DESCRIPTION OF THE INVENTION

Overview: The present invention is a puzzle in the form of a sphere comprising a spherical central support and a plurality of thirty-two visible segments of uniform thickness which forms an outer shell enclosing completely the said spherical central support. FIG. 1 is a perspective view of the preferred embodiment of this invention. The visible segments of the puzzle are delimited by seven planar sections through the center of said sphere which produce the great circles 12, 13, 14, 15, 16, 17, 18 on the surface of said sphere. The planar sections containing great circles 13, 15, and 17 are perpendicular to each other. As a result, the plurality of visible segments of the puzzle comprises twenty-four segments 40 with arcuate right isosceles triangular faces, and eight segments 50 with arcuate equilateral triangular faces. The puzzle is constructed in such a way (described below) that any hemispherical groups of outer segments separated by a sectioning plane can be rotated relative to each other along the sectioning plane. In FIG. 2, the left view shows a rotation about a cubical axis perpendicular to a plane containing one of the great circles 13, 15, or 17. The right view of FIG. 2 shows a rotation about a tetrahedral axis perpendicular to a plane containing one of the great circles 12, 14, 16, or 18.

Spherical central support: The spherical central support of this invention is an adjustment of an embodiment of the spherical puzzle with four axes of rotation disclosed in U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau) and illustrated in FIG. 4. FIG. 3 shows a preferred embodiment of the spherical central support, which comprises six segments 10 and eight segments 20 obtained by adding three mutually orthogonal crossing tracks 32, 34 and 36 to the prior art shown in FIG. 4, wherein each track has an arcuate T-shaped cross section and follows a great circle along the diagonals of the arcuate square segments of said prior art, by including a pair of outer lips extending toward each other to define a narrow outer slot and an inner enlarged sliding path.

Outer shell: The twenty-four arcuate right triangular segments of the outer shell are mounted on the crossing tracks of the spherical central support. As shown in FIG. 5 and FIG. 6, each outer segment 40 is provided with a leg 42 mounted on the inside of its right corner and an inwardly projecting foot 44, dimensioned to have a profile complementary to the profile of the cross section of the crossing tracks, thus being free to slide within and be retained by the crossing tracks via the projecting foot. Also, a group of four outer shell segments 40 positioned at the junction of two crossing tracks is also free to rotate slidably about its axis of symmetry, on top of segment 20 below, as shown in FIG. 7. The width of projecting foot 44 is dimensioned to be sufficiently large in comparison to the width of the narrow outer slot of the crossing tracks, to ensure the permanent retainment of segments 40 on the spherical center structure when they are slidably moved along crossing tracks or rotated at a junction of crossing tracks. Thus, outer segments 40 are free to slide along the crossing tracks of the center support and to slidably rotate as groups of four at a junction of crossing tracks on the spherical central support.

FIG. 8 is a perspective view of this invention with segments 50 exploded outward a constant distance from their installed positions. One segment 50 is fastened on top of an arcuate triangular segment of the central spherical support. The other segments 50 have no connections whatsoever to the spherical central support, but are held in place by the neighboring outer segments. The interlock between segments 50 and their neighbors is based on spring latching mechanisms installed on the sides of segments 50, with tongues protruding in complementary U-shaped side channels along the adjacent sides of their neighbors. FIG. 9 is an exploded view of segment 50. Every spring latching mechanism of segment 50 comprises an arcuate tongue 52 of uniform thickness slidably mounted in a slot on one side of said segment 50, which is urged by a spring 58 mounted behind said tongue to protrude from said segment 50 in a complementary slot 54 of the outer segment facing said tongue. FIG. 10 is a median cross section of the preferred embodiment of segment 50, which shows how a spring mounted in a cylindric slot behind a tongue holds said tongue in a small indentation outside the edge of said segment 50 by applying a tension behind said tongue. The sliding slots of tongues inside segment 50 are shown in FIG. 9 with phantom lines.

When protruded, the outer surfaces of tongues are engaged by the inner surfaces of the side tracks of slots 56 and prevent segment 50 comprising said tongues from falling out from the outer shell of the puzzle. There are eight side tracks for the tongues, one side track on each side of the outer shell delimited by a section along the great circles 12, 14, 16 and 18 shown in FIG. 1. Also, during rotations about tetrahedral axes, the protruded tongues are free to slide along said side tracks, and sometimes they collide with protruded tongues of segments 50 on the other side of the separating plane of rotation. When a collision between tongues occurs, the said tongues are pushed in directions opposite to the tension of their springs until they slide into their comprising segments 50 just enough to enable the sliding of said segments 50 beside each other.

Rotation about cubical axis: FIG. 11 is a perspective view of the puzzle subjected to a rotation about a cubical axis. Four outer segments are elided to enable the visualization of the interlocking between outer segments and the segments of the central core. The outer equilateral segment fastened on top of a triangular segment of the central structure is labeled 50′. Segment 50′ is called anchor because it blocks any potential sliding or rotation on the spherical central support of the visible segments located in the same hemisphere of rotation with segment 50′. Therefore, all outer segments in the same hemisphere of rotation with the anchor remain aligned with the segments of the center support below them. By contrast, the outer segments of the opposite hemisphere of rotation are forced to slide on the spherical central support: segments 40 bordering the plane of rotation are forced to slide through the crossing track along the plane of rotation; the group of four segments 40 at the pole of the hemisphere is forced to slidably rotate on the spherical central support; and the remaining segments 50 are forced to slide simultaneously with their neighboring segments 40.

Rotation about tetrahedral axis: FIG. 12 is a perspective view of the puzzle subjected to a rotation about a tetrahedral axis. Four outer segments are elided to enable the visualization of the interlocking between outer segments and the segments of the central core. The inner pieces of the spherical central support are forced to stay aligned with the pieces on top of them because the legs and feet of pieces 40 have no tracks available to slide on the center support, and as a result they will force segments 20 below them to rotate simultaneously. Outer segments 40 remain attached with their legs and feet to the tracks of the spherical central support, and outer segments 50 remain permanently attached with at least two protruded tongues to their neighboring segments. Another important feature of the tongues of segments 50 is the arcuate shape of their portion outside the sliding slot of their comprising segment. As a result, when the tongues of two segments 50 collide in the plane of rotation, they are pushed in said segments 50 until they can slide next to each other. Note that the temporary push of tongues 52 during this rotation affects only one out of three spring latching mechanisms of their comprising segments 50, which is insufficient to disengage said segments 50 to fall out from the outer shell of the puzzle.

Method of assemblage: The assemblage of spherical central support with segments 40 mounted on the crossing tracks coincides with the assemblage of Meffert's puzzle ball disclosed in U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau), with the only difference that segments 40 are placed on top of inner segments 20 prior to the assemblage of the spherical central support. A segment 50 can be assembled by squeezing springs 58 through slots 56 into their cylindrical slots, followed by the insertion of tongues 52 through their sliding slots in said segment 50. Afterwards, one segment 50 is fastened on top of a segment 10 of the center support, e.g., by means of a pin. Finally, every remaining segment 50 can be positioned in the outer shell of the puzzle by first pressing its tongues inside and next pushing said segment 50 inward between three segments 40 until it snaps into place.

Method of use: The visible faces of the puzzle are preferably marked with a predetermined pattern or coloring so that only one or a few relative orientations of its outer segments define a solution. For example, in the preferred embodiment shown in FIG. 1, every octant of the outer shell comprising one segment 50 and three neighboring segments 40 may be colored differently. Furthermore, the puzzle can be made more challenging to solve by splitting the face of every outer segment 50 into three arcuate triangular faces with one corner in the middle of the outer surface of the said segment. This would yield a spherical puzzle with forty-eight faces. The puzzle may be scrambled by a series of rotations by integer multiples of 90° about cubical axes and integer multiples of 120° about tetrahedral axes. The object of the puzzle is to return by means of a series of such rotations to the unscrambled coloring or pattern.

Since many modifications, variations and changes in detail can be made to the above described embodiment, it is intended that all matter in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. 

What is claimed is:
 1. A spherical sliding element puzzle comprising: a spherical central core which is an embodiment of the prior art U.S. Pat. No. 5,358,247 (U. Meffert and A. L. Chau) adjusted with three mutually orthogonal circular crossing tracks receiving legs and feet of some slidable outer segments; a plurality of thirty-two outer segments which forms a spherical shell completely enclosing the said spherical central core, the shapes of the said outer segments being determined by seven planar sections through the centre of the spherical core, such that three of the said planar sections are perpendicular to each other and cut the said outer shell into eight octants; the other four said planar sections are along the midpoints of the arcuate edges of the said octants, thus splitting every said octant into three arcuate right isosceles segments and one arcuate equilateral triangular segment; and the said outer segments being attached either to the central spherical core or to the neighbouring segments in a manner that enables rotations of hemispherical groups of segments relative to each other along the said sectioning planes.
 2. The spherical sliding element puzzle of claim 1 wherein each of the said circular crossing tracks forms a complete circle in the spherical central support along the diagonals of its arcuate square segments and includes a pair of outer lips extending toward each other to define a narrow outer slot and an inner enlarged sliding path; the arcuate right isosceles segments have legs attached to their inner side, which extend through the narrow slots of the corresponding tracks of the central core and have feet mounted on their inner ends for sliding in the inner sliding paths and for being engaged by inner surfaces to slidingly retain the said arcuate right isosceles segments on the support; seven of the arcuate equilateral triangular outer segments have a mechanism intended to keep them attached to the spherical core and to the neighbouring outer segments while being able to slide relative to them, the said mechanism being comprised of three spring-activated tongues installed on the sides of said arcuate equilateral triangular outer segments, which protrude in U-shaped side channels along the adjacent sides of the neighbouring segments and retract during collisions between said tongues, that may occur when performing to some hemispherical rotations; one arcuate equilateral triangular outer segment is rigidly mounted on top of a corresponding arcuate equilateral triangular segment of the said central support, in order to keep all the segments of the outer shell properly aligned on top of the corresponding segments of the central support after performing a complete hemispherical rotation by a multiple of 90° along any of the three mutually orthogonal planar sections of the puzzle, or after performing a complete hemispherical rotation by a multiple of 120° along any of the other four said planar sections of the puzzle.
 3. The spherical sliding element puzzle of claim 1 wherein the visible faces of the outer segments are marked with a predetermined pattern or colouring so that only a few relative orientation of its outer segments define a solution, the object of the puzzle being to start from a scrambled arrangement of its outer segments and to return to an arrangement corresponding to a solution by means of a series of hemispherical rotations.
 4. The spherical sliding element puzzle of claim 3 wherein the predetermined solution is given by assigning a colour to every group of four outer segments that comprises a spherical octant delimited by the mutually orthogonal planar section of said puzzle.
 5. The spherical sliding element puzzle of claim 3 wherein the predetermined solution is a raised relief on its outer segments. 